Contrary to commonly held views, giving newborns sucrose does not significantly reduce the pain they suffer while undergoing routine procedures shortly after birth, according to a new Canadian study that may throw the common practice into question.
"It means sucrose is not the panacea," said Anna Taddio, lead author of the study and associate professor at the University of Toronto's Leslie Dan Faculty of Pharmacy. "People need to know it's not enough."
The study's findings, published today in the Canadian Medical Association Journal, could have significant consequences for the way health professionals approach infant pain management.
In addition to minimizing discomfort, controlling a newborn's pain during medical procedures is important because it can affect how they respond to pain in the future and also play a critical role in the nervous system's development.
"If you don't treat pain there may actually be a physiologic consequence," Dr. Taddio said.
Sucrose is widely believed to activate the body's pain-relieving opioid system and is put into the mouths of babies before painful procedures as a way to avoid using medications whose effects on infants may be unknown or not well studied.
Although infants are routinely given a sugar solution as an analgesic during routine procedures that occur in the first few days of life, including blood tests and vitamin K injections, few studies have measured its impact on pain reduction, Dr. Taddio said.
"We actually didn't know how well sucrose was working for all the procedures that we do," said Dr. Taddio, who is also an adjunct scientist at Toronto's Hospital for Sick Children. "What was interesting and new about it is that we found that sucrose didn't work as well as we expected it to in the first day of life."
In the study, researchers examined a group of 240 newborns - some of whom had been given sucrose as an analgesic, and some who had received a placebo. The researchers considered newborns from diabetic mothers and non-diabetic mothers separately because babies with diabetic mothers had to undergo more heel lances, a painful procedure in which blood is taken from the heel in order to monitor their glucose levels.
In addition, newborns usually receive vitamin K injections and venipuncture, in which blood is drawn from a vein.
Surprisingly, researchers discovered that sucrose seemed to be a very effective analgesic during venipuncture, but not for the other procedures. After examining their facial and physiological responses, researchers determined that newborns who had been given sugar only experienced a "modest reduction" in pain compared with those who received placebo.
"Over all, it didn't really work as well as we thought," Dr. Taddio said.
Researchers used the established Premature Infant Pain Profile, which measures the baby's facial expressions, heart rate and oxygen saturation to gauge overall pain levels. They found that infants who received sucrose experienced an overall pain reduction of about 16 per cent, which they considered to be only a modest difference. When they examined pain during individual procedures, researchers found that while sucrose effectively reduced pain during venipuncture, it had no significant impact during heel lances or vitamin K injections.
Dr. Taddio said more studies need to be done to determine why sucrose doesn't appear to be a very effective analgesic for certain procedures. But there doesn't seem to be any harm in administering it, she said.
Medical professionals should explore methods other than administering sucrose to enhance pain control, such as giving babies pacifiers or other treatments, she said.
"People like sucrose for obvious reasons. Nobody's terribly afraid of giving sugar water. At the same time, it's not the answer for everything and it's not enough."
Another study being published today in the CMAJ found that applying a topical spray can reduce pain by 34 per cent in children undergoing intravenous procedures, compared with those taking placebo.
The study examined children between the ages of 6 and 12, not infants, however. The vapocoolant spray used is a rapid-acting alternative to topical anesthetics.